The club has an FCC license for some business frequencies that cover this area of california and parts of nevada.  The frequencies are:

151.700 MHz
151.760 MHz
154.5275 MHz
469.500 MHz
469.550 MHz

The leader of whatever run you are on will pick the frequency, usually one of these or one of the GMRS/FRS frequencies if some people only have little motorola type walkie-talkies.  There is sometimes interference in urban areas as fast food drivethrough headsets are low power and can be licensed on the same or close frequencies.  Send a message to Tyler (club name "Tyler - K6TLR") and he can set you up with the legal programming file for the radio if you aren't already HAM licensed.